Another advantage of the modal expansion is that frequency-dependent
characteristics of hearing can be brought to bear. Low-frequency
resonances can easily be modeled more carefully and in more detail
than very high-frequency resonances which tend to be heard only
``statistically'' by the ear. For example, rows of high-frequency
modes can be collapsed into more efficient digital waveguide loops
(§8.5) by retuning them to the nearest harmonic mode series.